Attachment for dental engines



(No Model) B. D. EDDY.

ATTACHMENT FOR DENTAL ENGINES.

No. 462,896. Patented Nov. 10, 1891.

UNlTED STATES PATENT OFFICE.

EARL D. EDDY, OF SAN MATEO, CALIFORNIA.

ATTACHMENT FOR DENTAL ENGINES.

SPECIFICATION forming part of Letters Patent No. 462,896, dated November10, 1891'.

Application filed January 16, 1891. $erial No. 378,059. (No model.)

To all whom it may concern.-

Be it known that I, EARL D. EDDY, of the town of San Mateo, in thecounty of San Matee and State of California, have invented certain newand useful Improvements in Right- Angle Hand-Pieces or Attachments forDental Engines, of which the followingis afull, clear, and exactdescription.

This invention has relation to attachments for dental engines; and itconsists in certain peculiaritiesin the construction, arrangement, andcombination of the several parts, substantially as hereinafterdescribed, and particularly pointed out in the subjoined claims.

The objects of the invention are to provide a right-angle hand-piece orattachment for dental engines in which, first, the facility for quicklychanging the tool will be increased; second, the tool will be held withgreater security; third, all wear at the point of union between thelocking-flange and the head will be taken up; fourth, the tool willoperate with less noise than those now in use, and fifth, the tool willoperate with greater comfort to the patient. These objects areaccomplished by the mechanism illustrated in the accompanying drawings,in which- Figure 1 is a longitudinal central section of that portion ofa right-angle hand-piece or attachment involving my improvement, andshows the tool locked in place ready for the rotary motion or drivingpower to be applied. Fig. 2 is a similar view showing the tool removedand the device ready for the insertion of a tool. Fig. 3 is a transversesection of the instrument at the longitudinal center of the tool,showing the tool locked in position, as in Fig l. Fig. 4 is a frontelevation or face view of the instrument with the sliding tool-lockremoved, so as to show the flange e.

attached and spiral spring d removed from the projection C. Fig. 8 is aplan view of the upper surface of a right-angle hand-piece or attachmentfor a dental engine, showing the rectangular recess a in the body orframe of the instrument and also the plane surface on which the slidingtool-lock H is operated. Fig. 9 is another form or shape of flange eandgroovef shown in Fig. 4. Fig. 10 is a plan view, side elevation, of aright angle handpicce or attachment for a dental engine containing myimprovements, showing the sliding tool-lock closed and the tool absent.

The hand-piece to which my improvement is applied consists of the stockAand the toolhead B, integral with said stock, but at right anglesthereto. This stock Ais formed with a mortise-shaped rectangular recessa, and the head B is formed with a groove f, said recess being designedto contain and facilitate the operation of a lug b with its cylindricalarm 0 and spiral spring (I, and said groove to receive flanges 6, formedon and projectingfrom a sliding tool-lock H, the under surface J ofwhich lock is in contact with the upper surface i of said head. Thesliding tool-lock H is also formed with an inward projection K, whichengages a groove 42, formed in the head of the tool a, andlocks saidtoolin place, and with an apertureL,through which the head of said toolpasses before its engagement with the locking-flange K. The lug I) issecured to said sliding tool-lock by a screw g. A recessed seat isprovided on the under surface J of said sliding tool-lock for the pur-'pose of holding said lug in such position that its cylindrical arm orprojection 0 will always be parallel to the direction in which thesliding tool-lock moves in its operation of looking and unlocking thehead of the tool 01.. The cylindrical arm 0 is simply a projection fromthe perpendicular face of the lug b, and is designed to support thespiral spring cland also to form a stop for the tool-lock H when thelatter is forced open to receive the head of the tool n, as will beclearly seen on reference to Fig. 2. One end of the spiral spring d hasits bearing on the face of the lugband the other end thereof finds itsbearing on the opposite face of the recess a, and said spiral spring isof such tension that it may be contracted sufficiently to open thesliding toollock H by a moderate pressure of the thumb or finger appliedon the upper surface thereof just back of the aperture L, which surfacemay be beveled for this purpose. The functions of this spiral spring (Zare, first, to hold the sliding toot-lock securely closed at all times,except when forced open for the pur- 7 pose of changing or removingtools, and, second, to take up the Wear of the locking-flange K, Figs. 1and 2, which it continues to do until the back of the lug Z) comes incontact with the Wall of the recess a, and it furthermore compensatesfor slight variations in the size of the different tool-heads.

M designates the hollow shaft, which contains the shanlcof the tool aand receives motion from the driving-shaft O, at the end of which is apinion 12, that engages with a similar pinion p in the hollow shaft M,thus forming a right angle in the direction of the rotary motion, and byreason of the close frictional contact with it of said tool communicatesits motion to the latter.

Having thus described and illustrated my invention, I claim as new anddesire to secure by Letters Patent 1. The herein-described attachmentfor dental engines, consisting ofan angular handpiece adapted to hold atool and formed with a recess, a sliding tool-lock adapted to engage thetool and provided with a lug projecting into said recess in thehand-piece and having a horizontal arm, and a spiral spring encirclingsaid arm and having its abutment against one wall of said recess andsaid lug.

2. In an angle attachment for dental engines, the stock, the tool-headextending at right angles to the stock, and the headed tool passingthrough said head, in combination with a spring-actuated slidingtool-lock having flanges engaging in the head of said tool.

3. In an angle attachment for dental engines, the tool-head and theheaded tool passing through said tool-head, in combination with asliding tool-lock having an opening to permit the insertion of the tool,and a flange to engage the head of the tool.

4. In an attachment for dental engines, the combination of thehand-piece, a hollow shaft extending vertically therethrough, a headedtool extending through said shaft, a sliding tool-lock adapted to engagethe head of the tool, and means for imparting motion to said hollowshaft.

5. In an angle attachment for dental engines, the tool-head, the stockhaving a recess, and the headed tool passing through said toolhead, incombination with a sliding tool-lock having near one end an opening topermit the insertion of the tool, and a flange to engage the head of thetool, a lug projectinginto said recess from the opposite end of saidtool-lock and provided with a horizontal arm, and a spiral springencircling said arm and having its abutment against one wall of saidrecess and said lug.

In witness whereof I have hereunto set my hand this 1st day of January,A. D. 1891.

EARL D. EDDY. Witnesses:

O. M. MoRsE, I. R. GooDsPEEn.

